Control means



W. STABLEEN CONTROL MEANS Filed Jan. 6, 1932 mm a w @W m m 7 m T..L TM wm V r m n W. I 7 w 4m-ww 2 INVENTOR WILHELM STABLEIN BY W/ ATTORNEY mama Feb. 14, 1193 UNITED STATES PATENT- osrlcs wmr'mml: srls'ssnnm, or BERLIN, GERMANY, assmnoa 'ro atmnmamn ILEI- rmcn'ars GESELLSCHAFT, rnrnnmcn mL, or BERLIN, 'enmran, acom'onanon or annuity common MEANS Application filed January 6, 1982. Serial No. 585921, and in Germany October 2, 1830..

This invention relates to control means, and in particular to means for the selective transmission of two signals by modulation of one carrier wave.

For the purpose 'of selective transmission of two signals, as is known in the prior art, two distinct radio frequencies may be used which are coordinated, respectively, to the two signals. However, it is also known in the earlier art that the two desired signals may be'transmitted on a single frequenc each of the signals having ltsbgwn modu ation frequency, differentiation in insured by different modulation of one an the same carrier wave.

Now, according to the present invention a simpler arrangement is created by that only one of the two signals to be distinguished is differentiated or characterized by modulation, while the other signal is transmitted unmodulated. On the one hand, this means a simplification in the transmitter uipment insofar as another modulator-device 1s dispensable, while, on the other hand, such electrical filter means as have heretofore been provided at the receiving end for the purpose of separatin the variousfreuencies or modulation requencies can be is nsed with, for separation is accomplis able by the aid of a simple relay scheme.- There is shown in the accompanying drawing, by way of example, an arrangement ada ted to wired wave on.

esen' endisdenotedbyhandthe receivin end y 2. Atthe transmitter end isprovi ed a generator vor oscillator valve, or relay of that type wherein the input circuit is connected with a radio uency source indicated at 4. This source is included in the grid circuit of the oscillator or relay tube 3. Whenever the unmodulated signal is to be sent out, the switch, dis closed and as a result the radio frequency source 4 is connected with the grid G. By means of the coupler coils 6 and the coupling condensers 7 oscillations having the fragile of the source 4 are then fed fromthean a, cathode circuit of tube 3 into line L. When the modulated signal islto be transmitted, the switch 8 is closed. The

50 aim modu nerator 9 and over ceiver 11, merely indicated schematical y, is I connected by way of the coupling condensers 10 to the line L. "The said radio frequency radio frequency source 4 and the modulation wave source 9 are now connected in series receiver 11 has in series in the out ut thereof the direct current relay 12 an the primary' winding of an alternating current transformer 13. The secondary winding of said transformer is connected in series with.

a rectifier 14 and direct current relay winding 15. Whenever unmodulated radio fro- I quency currentis transmitted, a pure'direct current will flow in the audio frequency circuit of the receiver 11 with the result that onlyzthe'relay 12 is caused to respond and is caused to close its working contact 120- in the circuit IR. When modulated radio frequency current is transmitted, then a. direct current having an alternating current superposed thereon will flow in the audio frequency circuit of the receiver 11. The alternatin the secon ary end of the transformer 13 a corresponding potential which is rectified by the rectifier 14 and which causes the; relay 15 current component induces in ,1

to respond. In this relay the working con l tact 15a included in the circuit HR is closed,

while the back contact 151' included in circuit I will be opened. Simultaneously with the energization of the relay 15, however, also the relay 12 becomes energized so that the working contact 12a will be closed also when the signal modulated with alternating IR, however, this circuit will be'opened so T ecircuitsm and when transmitti carrier frequency and current is transmitted. By the opening of I the back contact 151- contained in the circuit "up amtus ior ..mi m a I 1M carrier uency respectivel For example, in a i'idio or wired radio signaling s tem, a rinter may be rendered operative y circuit to receive and record the messages sent through circuit 11R,

Having thus described my invention and the o ration thereof, what I claim is:

1. gignallin apparatus comprising v a transmission c annel, transmittin apparatus including a high frequency t ermionic generator havin' its out ut electrodes connected with sai channe a source of high uenc connected with the input electr es 0 said generator, a source of modulatiug frequency in series with said'input circuit, switching means in said circuit, said switching means being adapted to short-circuit said modulating requenc source a receiver at the other end of sai channel, said receiver having an output circuit includin an alternating current relay and the primary of an alternating current transformer in series, detecting means in series with the secondary winding of said alternating curoutput circuit including a relay, detecting means coupled with said output circuit, a second relay coupled with said detecting means, a plurality of work circuits, circuitlays.

WILHELM STABLEIN.

rent transformer, a direct current relay connected with said detecting means, a pluralit of work circuits, contact means in one 0! said work circuits associated with each of said relays, and contact means in another of said circuits associated with one of said relays.

2. An arrangement for the selective transmission over a line of two signals by means of a single carrier wave comprising, a source of high frequency oscillations, means for capacitively coupling said source to said line,

a source of modulating energy connected with said hi h frequency source, switchin means for s ort-circuiting said source 0 modulating energy whereby said carrier may be sent out over said line modulated or un- -modula ted, a receiver connected with said line,"a pair of signalling, circuits, a. pairof r'elays connected between said receiver and said signallingcircuits, one of'said relays being responsive to energy in the output-of said receiver to close "one of said circuits when said carrier is unmodulated, both of said relays being responsive to energy in the output of said receiver to close both of said circuits when said carrier is modulated, and additional means for maintaining one of said circuits open when said carrier is modulated.

3. Signallin apparatus comprising, a transmission c annel, tr smitting apparatus including a source of high frequency oscillations connected with said channel, a source of modulating potentials connected with said source of high frequency oscillations, switchin means, said switching means being a apted to short-circuit said modulating potential -source, receivi means aaociated with the other end of sai channel, said receiving means having an 

